How to: Validate special characters

Good day everyone,

This week I would like to share a class used to validate special characters.
I couldn’t find any propertie on table fields like “Block special characters”, because of that I am using a class that validate each character of a string using containers. Normally I call this class by Overriding the method ValidateField() from table.

This is how it works on ValidateField():

public boolean validateField(FieldId _fieldIdToCheck)
{
    boolean ret;

    ret = super(_fieldIdToCheck);

    if(ret)
    {
        switch(_fieldIdToCheck)
        {

            case fieldNum (LogisticsEletronicAddress, Locator):
                    ret = ValidateCharacter::validateCharacter(this.Locator) ;

                    if(!ret)
                        error( "The eletronic address has invalid characters" );
                    break;
        }
    }
    return ret;
}

For example, I have used the Table LogisticsEletronicAddress which is responsible to save contact information like e-mail and telephone. I will check if I am validating the field Locator and then call my class. Suppose I have typed “264-497=3131″.

This is my class:

public static boolean validateCharacter(str _name)
{
    System.Text.RegularExpressions.Match    regExMatch;
    boolean                                 isValid = true;
    int                                     length;
    int                                     counter;
    container                               specialCharacters;
    str                                     value;
    ;
    
    // Here I insert all the special characters I want to validate.    
    specialCharacters = conIns(specialCharacters,1, "/");
    specialCharacters = conIns(specialCharacters,2, "[");
    specialCharacters = conIns(specialCharacters,3, "]");
    specialCharacters = conIns(specialCharacters,4, ";");
    specialCharacters = conIns(specialCharacters,5, "=");
    specialCharacters = conIns(specialCharacters,6, @'\');
    specialCharacters = conIns(specialCharacters,7, ":");
    specialCharacters = conIns(specialCharacters,8, ",");
    specialCharacters = conIns(specialCharacters,9, ".");
    specialCharacters = conIns(specialCharacters,10, "!");
    specialCharacters = conIns(specialCharacters,11, "-");
    specialCharacters = conIns(specialCharacters,12, "(");
    specialCharacters = conIns(specialCharacters,13, ")");
    specialCharacters = conIns(specialCharacters,14, "*");
    specialCharacters = conIns(specialCharacters,15, "&");
    specialCharacters = conIns(specialCharacters,16, "^");
    specialCharacters = conIns(specialCharacters,17, "#");
    specialCharacters = conIns(specialCharacters,18, "@");
    specialCharacters = conIns(specialCharacters,19, "_");
    specialCharacters = conIns(specialCharacters,20, "$");
    specialCharacters = conIns(specialCharacters,21, "%");
    specialCharacters = conIns(specialCharacters,22, "?");
    specialCharacters = conIns(specialCharacters,23, "+");
    specialCharacters = conIns(specialCharacters,24, "{");
    specialCharacters = conIns(specialCharacters,25, "}");
    specialCharacters = conIns(specialCharacters,26, "<");
    specialCharacters = conIns(specialCharacters,27, ">");
    specialCharacters = conIns(specialCharacters,29, "~");

    // I set my container length size.
    length = conLen(specialCharacters);

    // Looping through the container
    for (counter = 1; counter <= lenght; counter++)
    {
        // Getting the container value.
        value = conPeek(specialCharacters, counter);

        // Here I use the method StrContains(), it will check the String 
        // character-by-character and return true if it matches the desired value.
        if(strContains(_name, value))
        {
            isValid = false;
        } 
    }
    // Return validation result.
    return isValid;
}

I have used all the special characters that I know of but feel free to add as much as your client requires :). This code will check the string “264-497=3131″ character-by-character and match all the 28 special characters and return it as false (Let’s forget that my telephone number accepts alphabetical characters haha).